Do you sync your iPhone with your MacBook? If so, sync is a likely vector.
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this.joshDec 3 '12 at 6:14

Does your iPhone also redirect, if it's not connected to WIFI?
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KaoDec 3 '12 at 8:25

This sounds more like a DNS issue then malware. The ultimate test is to wipe the iPhone and see what happens. I can nearly guarantee that your iPhone isn't infected with malware.
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RamhoundDec 3 '12 at 16:17

This trojan can only be obtained, by you actively downloading and installing it, probably masked as a trustworthy program.

As for antivirus, there's no AV Software out there, that will make sure that you can't obtain a virus. The best advice I can give you, is to use common sense when downloading, and try to verify the source. AV's tends to give people a false sense of security.

Thank you. I will go over this once i get home. See above, issue 'magically' went away. I went off the home wifi to the library wifi which (i don't have proof of this) may have cleared the issue for the iphone. I don't honestly remember if issue persisted while i was in the library.
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JamDec 3 '12 at 18:51

If your iPhone starts acting weird, when it gets back on the WIFI, you should check your router, and see if it's been compromised, or any DNS rules have been added.
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KaoDec 4 '12 at 10:54